In preparation for the planet-finding missions DARWIN (ESA) and the Terrestrial Planet Finder (NASA) a range of precursor missions are being defined, aimed at testing and validating the technology needed to make the planet-finder missions feasible from a technology point of view. In Europe the SMART-2 mission is meant to test high critical technologies for the DARWIN and the gravitation wave mission LISA (ESA/NASA). The mission SMART-2 consists of two spacecraft. These two spacecraft will demonstrate the feasibility of formation flying related to the DARWIN mission. Furthermore SMART-2 will simulate a stellar interferometer by combining white light from the two spacecraft in an interferometric focus. Two fringe-tracking modes of operations will be tested. In the standard fringe-tracking mode an onboard optical delay line is commanded to keep the optical path difference within the coherence length of the combined light. In the second mode the optical path difference is equalised by commanding the FEEPS (Field Emission Electric Propulsion) thrusters. In both modes a range of metrology systems are needed to measure deviations from the nominal configuration of the two spacecraft. Here we report on the work related to metrology systems for the SMART-2 mission needed to measure the longitudinal distance with nanometer accuracy and the lateral position of one spacecraft with respect to the second spacecraft with 5 mm accuracy. We discuss the present concepts for the metrology systems for SMART-2 and we will elaborate on the possibility to integrate the different optical metrology systems into a single system reducing complexity, risks and mass.
Metrology concepts for a space interferometer mission: SMART-2
Interferometry in Space ; 2002 ; Waikoloa,Hawai'i,United States
Proc. SPIE ; 4852
2003-02-26
Conference paper
Electronic Resource
English
Space Interferometer Mission (SIM) Instrument Design Concepts
British Library Conference Proceedings | 1999
|The Laser Interferometer Space Antenna mission
AIAA | 2000
|The Laser Interferometer Space Antenna mission
IEEE | 2001
|